Steering mechanism for automobiles



y 1933. R. H. CHILTON STEERING MECHANISM FOR AUTOMOBILES Filed May 2, 1950 nt d July 18, 1933 I COMPANY, OF DAYTON, OHIOLA CORPORATION OF DELAWARE srnmtrneuacnnnrsmr roaau'romonxiins dp'plicat io n filed May 21930. Serial n5.-449; 42..

i This invention relatesto the steering gear for automotive yehiclesi and the like and .is especially useful as a joint between a-steering drag link and an actuatingpitmanthere for wherebytoreduce or preventthe phenomena known as front- Wheel' shimmy in presentdayautomobiles;

An object of the inventiongis toprovide a. strong, simple5 and efficient swivel joint be-' tween a pitrnan and a thrustlink which will cause a small translation of said link rela tive to said pitman upon acha'nge'of angularity between said linkand pitman.

= A more specific object is'to p'rovide such a joint between. the actuating pitniian a nd the drag linkwhich causes thesteeringj movement of the front Wheels of an'automobile,

. whereby the front endof the drag link-may j ferred embodiment :ofone form ent invention is clearly shown. A

The left front leafjspring -l2 is fixed to the: axle; 11 in any usual or suitablemanner and has a pivot shackle 13 connecting. its front] end tothe;side rail lO and extension f shackle l4 connectingits rear end thereto.

move freely upand down in the substantially arcuate path prescribed therefor by the front leaf spring Without causing front wheel shimmy and allied phenomena;

Further" objects and advantages of the V present invent-ionwillibe apparent fromthe following description, reference being h'adito the accompanying drawings. wherein a pre- Inthedrztwing? j- V 'Fig. l'is a diagrammatic View illustrating the use of this inyentionona steering gear of a present'day automobile. -l I Fig. 2 is a yerticalsection through the joint connecting the end of the ,pitlnan withthe 35 l i rear end of the drag-link. L r Fig. 3 is a View similar to Fig.2 but draglink and Fig. 4.15 a horizontal section taken on line "10 designates the front end of gthexleft chassis SlClQITEtjl and llthe front Wheel axle.

The s'teeringpitman 15 is mounted-upon a transverse shaft 16 which *is rotated by the I the relative movement ofilthei parts upon a. change of the angle between} the axes of 't'he T j i I RALPH H. CHILTON, 0F DAYTON,.onioassmnoa-womnnfmmmi "MANUFAOTiIRI N G driver through any suitable and ye ll kno wn form of' mechani'smlwhich need not be here illustrated'f; "The drag link 20"co'nne'cts the" V.

loweriendof pitman 16 t0 the ball 21 onthje e'nd'bfthe arm' 22 which projectsinwairdlyfrom the-"steering knuckle for the" left front wheel. The' swinging of pitm-ai'i'lfi in a ver- .tical 'pljane'will obyio'usly move link' 20 in 'a 'foreand aft direction" which will obviously;

rotate the steering knuckle about its substantiallyl'vertical knuckle pin and causesteering Y "moyeinent ofthe frontiyvheelsn ,Tlie" m'ech'ae nismlso far describedi is exceedingly well [known and hence; needs no fu r'ther disclosure here.

- 'Due tothe fact"thatthejleafjspring1.2. is

preferably' pivoted to rail 10 at itsfront end '13as shown in'Fig'. 1, whenfthe front spring 12lisi. fieged ffor' any reason'gthe' left' 'front Wheeltogetherwith its steering knuckle and? 'ball;21*is constrained tomo've up ,or doyvn in .an approximately arcuate 'p'ath withpointl'3 as acenter 'as seen in the projected .QVieW shown in Fig; 1;. f r The substantially aruate 'line 2 5, in Figfl designatesfthe'path 'of vmovement of thec'e'nter of ball. 21 from -its normal jmsitioi'i' which is preferably sub I stantially :in direct line;between points .13

f and 19'when the frontwheels areinTstr'aight', r

'Fig. 1 shoWs loall21 moved upward along" path 25 from itsI1( )I". I I1alposition due to an up movement of; axle 11; .I-Ience when the left frontewheel mores up or down fr omfits normal position due to passing 'over road irregularity, or for any other reasomfthere will be atende nfcy' to pull thepitman15ina due to the sudden tension put upon the drag undetermined. '*1'. 7

NOW the prime purfi ose of .to provide a remedy for suchysteering' link 20, This action is j-thought to be the 1 initial we f iia' o ls s e r n "fir 'e such as steering heel kicksffront -yvheel.shin '-c inyfiront a'xletramp, etc. which phenomena- I re -now "Wellfkn OV Ilt but the causes thereofi f 'clockwise direction asseen in Fig. 1], Qilffail-J ing 'in that, there will be a force 'to bias the; front wheels to turn to the slightly," or; r [in fact both tendenciesoccur simultaneously I bles by providing aswivel oint between the:

I 7 is put upon'linkf 2051; such times.

. 32 (see Fig.

Pittmanand drag link which automati- Cally in effect'extends the lengthof linkQO when its front end moyes up or downdue to ball 21 following the fprescribed substantial- 1y arcuate path 2550 that little orno tens on Figs2, 3 and 4 illustrate the swivel oint of this invention. ,Pitinan 15 has an elongated carn whose long 'axis extends vertical ly as shown. This cam 30 is preferably shaped as shown with a central cylindrical; [portion 31 andheini-spherioalend portions A shank 34 projects later ally from cam 30 and is rigidly fixed to the.

. lower end ofgpitnfoan 15 'by anyi suitable means such as, by'the peripheral, serrat ons 35 shown in Fig. &. Link QOlias an-enlarged a tubular end 36 providing an; internal shoulder..3'(- therein.

7 A cani seat 40 Its-inserted within the tubular end 36,.againstshoulder,

I 5. 31' Seat iO'h'as-a cylindricalcamsurface 41 whichpfits s'nuglyagainst the cylindrical portion 310i? cam 30when the parts are in the cam 30 as shown in. Fig; Qand. theAstlfQDQ;

' coil compressionspring;5l inserted anc lcoin pressed thereagainst by the retaining plug 52 threaded into the; end of portion 36 llPlug 52 has I a. transverse slot 53 therein through v -ewhicha-eross pin154 maybe inserted to zpre vent loosening of the screwjalug. .52. 'The -j vslida'blecam seat hasfa cylindrical cam H surface 42 which -.corresp0nds to the radius r of cam-30 as-see'n from Fig. 4."

" front wheels are straight l ahead position canrffidwill have its cylindrical portion gl. fengagingthe opposed ca n surfaces'tl and M ;A:2,Qa s shownwinFig. 2. Ifnow theleft'frontrh el i mo ed e the tow d na W: from the side rail 10 due to theautomobile; aassingfover a road irregularity, thef-ronti' end: of drag link 20 will befraised or loiwf eredaccordingv to the substantially arcuate path 25 ofthe ba1l21 This obviouslywill: H i i 1 ehae e the ang1e*A-betWI thQ-. Proiectd" fms be tempted cmmng center lines'oi link 20 and pitinfan '15 a 3 illustrates i this-angle A? materially dee creased and shows theaction' of the elongat-li N I ed cam 30-a-t such time; CaInBQ fOrces the cam seats 40' and 50. further apart'again st th e urge of thelconipression spring '51 and in so doing the geometrical? central 1 0int 19 of:

, c arn;3 O moves along theaxis o f-link 2O fur-- L-ther away from cam surface 4:1 In ,other 1 words the link 20' is translated bodilyto the lefttasshown in Fig.1) relative to the cent'er 1190f c'anaBQ. Theshape and dimensions In the operation'ofthe device", when thej of cam 30 areypr eferably' so chosenfthatflink 20 is translated or shifted-to the ieft such an amount as will permit its front end to follow; the prescribed path 25 shown in Fig.1

without puttingthe l'ink20 under tension;

How-ever, any translation otlink 20 according to this 1nvent1on reduces the steerlng troubles mentioned hereinabove, that is, the translat-J ing movement need not be exact, to be bene ficial. "If necessary the coil spring 5111133 "yield to'perinitthe' front end of link 20 to follow path25. f'Forordinary steering of the-"car by the driver, ca n30 moves the link 20'f0re and aft. in the manner ofan ordinary ball and socket joint, the coil springfil being sufficiently strong toordinarily move link 20 to the rear without further compression; when; it i is .de-

sired to bias the front wheels. to turn to the 1 left. During such'steering the caminingac 8 7' 'tionofcam' 30 v takes-place, but has a useful rather thanharmtul efiect: since .gtheicam 30 "willtend-to stop when its cylindricalportion 7 y 3l'jis flat against thecamfseats 41, and L2 (as g I shown in Fig. thatis, the steering-media p nis'in-fwill tend to return to and remain, in

the: position for "straight-ahead runningi The free horizontal swinging of the frontendf oi linkQO is permitted by the rotation of thecylindrical.surfacestland 421'11pon;the cam 9 30*(sfee Fig. 4),'the shankBiniO ing in the M slot .38 provided therefor inthe tubularp0rtion- 36. Itwill be noted that when the 'angle A isias shown in Fi'giB, the-spherical ends 32 of cam some engage the .camsur' faces 41 andj4c2 throughout their complete arcs. Hence there will always be (suflicient*- a bearing surfaces between cam 30anditsseats and also the horizontal swinging of link will always be freely permitted.

0 VVhileI have shown and described-the joint of this invention as ap plie'd only at the rear Jendofthe drag link it m y be desired'in some casesto substitute it fort-he ball andesocket joint at; the front end thereof linstead, or "it may bejapplied to bothi; ends of the drag link; the action of eacHjOint'being the-same 1 as described in detail above. i 1

-lWhile the .forrn of embodiment. of. the presentinventi'on as hereln d sclosed, constitutes a preferred form. it is" to be understood; that within the (Vhatis claimed is'asffollows sc ope of the r clairns which-follow.

corresponding 'elongated seat fixed to jsa'idi link and engaging one'side ofsaidielongatedf cam, a second cam seat retained in sai dflinki j i" and means yieldably urging the second cam.- seat againstthe othersideot said cam,

humane? 1 by; a change of? angularitj between said link and pitmancauses a longitudinalltranslatio of sai'dlink relative to said pitmanfl A to the end of said pitman, a cam seat engaging one side of said cam and held fixed upon said llnk, a second cam seat engaging the other I side of said cam and yieldably pressed thereagainst, said two cam seats engaging opposite sides of said cam longitudinally of said drag links, said cam and cam seats being so shaped that a changeof angularitybetweensaid link and pitman causes a longitudial translation I o'fsaid link relative :to said pitlman.

i i 3. In a steering gearfor automotive v'ehi cles, adrag link foractuating the steering,

movement of the front 'road wheels, a swing-r ing pitman having a swivel Joint w th'said drag link, said joint comprising: a'ca'm fixed to the end of said pitman, ajca'm' seat engage ing one side of said cam and held fixed upon said link, a-second cam seat engaging the other side of said cam and yieldably pressedf th'ere i against,'said two cam seats'engaglng opposite sides of said cam longitudinally of said drag links, said cam and cam seats be ng so shaped that a change of angularity between said link and pitman causesja'-.separating in arelative link. i a

movement between said cam seats resulting longitudinal translation of said 4, Ina steering gear for automotive vehicles, adrag link for actuating the steering movement of the front road Whee1s, a

' saiddrag link, saidjoint comprising: an

elongated cam circular in transverse section fixed to the end of sa d'pltman, a cam seat circularin transverse section and engaglng l and ipitman causesa longitndinal transla one side of said cam and fixed to said link, a second cam seat engaging the oppos te slde of said cam and yieldably -forced thereagainst and supported by saidflink, said two cam seatsengagingopposite sides of said cam longitudinally of. said drag link, where by a change ofangula-rity between saidlink tion of said link relative to said pitm'an,

movement of the vfront road wheels, a swing? ing pitman having swiveljointwith said drag link, said joint comprising: an elon-g gated cam having' substantially fparti spherical ends fixed saidpitman, a cam" seat cylindrical in transVersesectmn engaging oneside of SELlCl cam andfixed'to said link, ,a second cam 'seatengaging the op positc side'of said 'cam and yieldably forced thereagainst and supported by said link, said two cam seatsfengaging' opposit sides,

bf saidearn longitudinally of. said di ag link,

whereby a change ofangularity between said andg'pitman causes a {relative longitudinal t-rfan'slationof said "link and, .where by 'a 1 transverse swinging of saidlink ,is' permitted 1 without "relative 6'. In a steeringgearlior, automotive. Ve-i hicles, a drag-link for actuating, the steering; A V 7 movement'of the'front road wheels,'a swinging pitmanjghaving a swivel jointwithsaid drag link, said joint comprising: an elon- -gated-cam fixed to said'pitman s'o that the long axis or saidfcam extends substantially perpendicular to the link axis 'whenQthe linkf'and Y pitman causes a relative so a parts are in normal position, a cor'r'esponding'elongated'cam seatnfor'said cam fixed to said-link; means for yieldablyforcingsaid link toward said elongated cam tof cause pressure engagement-30f said camand seat, whereby-a change of angularity between saidx; v

7..In combinatiom'a swingingpitman a' thrust link, a universal swivel joint connect-5' ing said pitnian "and slink-comprisi ng:"an" i elongatedcamfixedto said" pitinan, a correspondingelongated cam seatlengagingone,

side of said'cam and ifixedlto-said link, means for =yieldablyf, forcing said link toward! said cam to cause pressure engagementlbetween said seat andcam,;the long axis of said elon-g, gated cam and cam seat'extending -substantially perpendicular to the link axis, where by a change of angularitybetween'said link and pitman pausesv aflongitudinal t'ran'sl'a-- tion of said link relative tosaid pitman I 8." In-combination, a swinging pitman a swinging pitman having a sw vel ]o1nt w1th thrust link, a universal swivel joint 'connecting said pitman and link comprising anelongatedcam ahaving substantially 'partisphericalends fixed to. Said pitman, ane'lonof angle between said linkandfpitrnan causes to said ,pitman;v

to said link, a second seat, 'slildflbly suppoi'ted- V v a translation movement of said linkrelative" 5. In a steerlng gear for autoinotive ve- J i a V hicles, a drag link foractuatlng the steerlng 9 mb ma g g 'p n; a1 a thrust link, a universal swivel j oint coniiecting said pitmanand linki comprising; an elongated cam fixed toisaid'pitman, a cam,

'seatlen'gagingone side of saidca inj and fixed by said flink andl'yield'ably{forced against the other side oif said elongated'cam, the long i I axis of said eIongated-camandcamfseat ex tending substantially perpendicular to the linkfaxis', whereby a change of,anglebetween 10; Incombination; a swm gmg'pitman, a.

thrust link, a swivelrjoint connecting said H link relative to said pitman upon'a change of angle between said 1ink a1id'pitman. 1

' ALPHQHQ CHILTON,"

V 7 said lin'l i a nd-pitmaneause a translation -saie'l linkmelative;tefsaidjpitman, ,7

pitnian and comprising: a camr'fixed to one Of said parts, a cam follower fixed to the ether of sai d partsfend means folr lirging. I

said em and cam follower'ihtb pressure con tactpin'ra direction longitudinally-0f the axis of sa-id link s'aideam and follower being so as'sociatedas-Ito force's; translation of said 

